The present invention is directed to antimicrobial compositions including 2-(decylthio)ethanamine as the active agent which have lower freezing points than known compositions.
2-(Decylthio)ethanamine (hereinafter referred to as "DTEA") is a compound known to possess antimicrobial properties (see, for example, U.S. Pat. Nos. 3,291,683; 4,816,061; and 4,982,004). Compositions including DTEA are often used in cooling water towers, air washing systems and in other outdoor applications. A typical commercial DTEA composition, comprising 15 weight percent DTEA, 15 weight percent propylene glycol, and the balance water, typically begins to form crystals at 10.degree. C. Prior to its use, a DTEA composition is often stored in unheated areas and can be exposed to temperatures and conditions which can cause the DTEA composition to freeze. Such freezing often causes the DTEA composition to separate into different phases or a precipitate to form.
It would thus be desirable to develop antimicrobial compositions with DTEA as the active agent which have lower freezing points than known compositions. However, any additive to the DTEA composition which would help to lower the freezing point of the composition should not substantially affect the composition's antimicrobial properties. Also, any such additive should help to lower the freezing point of the composition for an extended period of time.
The present invention solves the above-indicated problems by providing antimicrobial compositions including DTEA as the active agent which have lower freezing points than known compositions, which remain stable for long periods of time, and which possess essentially the same antimicrobial efficacy as known compositions.